When to Say a or an

The indefinite article is a or an. But how do we know when to say a and when to say an?

The rule is really very simple. It depends on the sound at the start of the following word. (It does not depend on the way we write the following word, it depends on the way we say it.)

a + consonant sound

If the following word starts with a consonant sound, then we say a.

a cat
a game of golf
a human emotion
a Peruvian
a very fat woman

an + vowel sound

If the following word starts with a vowel sound, then we say an.

an apple
an extremely easy job
an interesting film
an old man
an umbrella

The importance of sound

Normally, we pronounce consonant letters with a consonant sound, and vowel letters with a vowel sound. But there are some exceptions. The rule about a or an is still the same. You just need to think about the sound, not the writing. Look at these examples:

vowel letter with consonant sound
a European country you-ro-pe-an
a one-day conference won-day
a university you-ni-ver-si-ty
 
consonant letter with vowel sound
an honest man on-est
an hour our
an FBI agent eff-bee-eye

See also Linking